Itaconic esters of 1,2 alkane carbonates, polymers, and copolymers thereof



United States Patent r 3,225,008 ITACONIC ESTERS 0F 1,2 ALKANECARBONATES, POLYMERS, AND COPOLYMERS THEREOF Gaetano F. DAlelio, SouthBend, Ind., assignor to Scott Paper Company, Philadelphia, Pa., acorporation of Pennsylvania N0 Drawing. Filed May 21, 1962, Ser. No.196,430 17 Claims. (Cl. 260-775) This invention is concerned with newmonomeric esters of itaconic acid and polymers and copolymers derivedtherefrom. Specifically it relates to itaconic esters of the generalformula or-nooo-J in which R represents H, a saturated aliphatichydrocarbon radical containing one to eight carbon atoms, and R; Rrepresents an alkylene dioxolone radical of the structure beta, omegaalkane triols containing three to six carbon atoms in the alkane chainhaving the formula wherein n is an integer having a value of one tofour. Thus, the new monomers of this invention are the itaconic estersof the 1,2 carbonates of 1,2,3 propane triol; 1,2,4 butane triol; 1,2,5pentane triol, and 1,2,6 hexane triol.

Itaconic acid is a dicarboxylic acid, and accordingly, the itaconicmonoand di-esters of the alcohols,

may be prepared and utilized in the practice of this invention.

In the monoesters, the remaining carboxylic group may be leftunesterified or may be converted to another ester group containing oneto eight carbon atoms as represented by R hereinabove. Illustrativeexamples of the aliphatic hydrocarbon radical R containing one to eightcarbon atoms are methyl, ethyl, propyl, butyl, amyl, hexyl, heptyl andoctyl, which may be linear or branched, such as isopropyl, secondarybutyl, isoamyl, secondary actyl, etc.

The esters of this invention can be prepared by a number of methods. Oneconvenient method is to use itaconic anhydride and the desired alcoholin accordance with the reaction CHzCO O ice CH =CC O O CH l1OHCI-IcrnoooJ 2) 2 This esterification reaction using the anhydride may beperformed simply by melting together the two reactants; but preferablyto avoid decarboxyl-ation or other side reactions, the esterification isperformed in an inert solvent such as heptane, hexane, benzene, toluene,dioxane, tetrahydrofurane, etc., and isolating the product. Themonoester thus formed can be used as such for the preparation ofpolymers and co-polymers, or maybe used as an intermediate in thepreparation of diesters by conversion to an alkali metal salt, such asthe sodium, potassium, lithium salt, etc, and reacting the salt with adialkylsulfate, thus CH =CC O O I I R2304 cmoo0J The new esters of thisinvention can be prepared also from itaconic acid, or the lower alkylesters thereof, and the cyclic carbonate of the alkane triol desired inaccordance with the general reaction CH1=CCOHR H0(o12n)..on--o n,

l CHQCOOR O O itaconic acid can be used in preparing the new monomers,in the presence of a hydrohalide acceptor such as tributyl amine, sodiumcarbonate, etc, thus CH2:CC 0 Cl 2H0 (CH2) u?H--CH H20 001 0 0 HAG andThe specific method used in the preparation of the monomer depends inmost cases on the monomer desired; for

example, when the acid monoester is desired, the method .using itaconicanhydride is preferred; when a symmetrical diester is desired theneither itaconyl dichloride, di-

methyl or diethyl itaconate is reacted with the cyclic carbonate of thealkane triol, and when a mixed ester, that is, an itaconic estercontaining a lower alkyl group together with the cyclic carbonate estergroup is desired,

then the itaconyl chloride lower alkyl monoester, or a lower alkyldiester is reacted with the cyclic carbonate of the triol as indicatedin the reactions hereinabove.

The esters of this invention are polymerizable monomers possessing apolymerizable CH =C structure and may be polymerized to formhomopolymers, or copolymers from a mixture of two or more of theseesters,

or copolymers from one or more of these new esters with other monomerscontaining a vinyl, CH =CH; a vinylidene, CH =C or a vinylene group,

late, ethylene dimethacrylate, etc.; the vinyl esters such as vinylchloride, vinyl acetate, vinyl stearate, vinyl benzoate, vinylchloroacetate, divinyl phthalate, divinyl succinate, etc.; thepolymerizable amides and nitriles such as acrylamide,hydroxymethylacrylamide, methacrylamide, itaconic monoamides, itaconicdiamide, acrylonitrile, methacrylonitrile, etc.; the alkenyl arylcompounds such as styrene, o-methyl styrene, p-methyl styrene,alphamethyl styrene, the chloro-styrenes, divinyl benzene, diallylbenzene, etc.; the monoand polyallyl esters such as allyl acetate,diallyl succinate, diallyl phthalate, diallyl maleate, diallyl fumarate;the vinylidene compounds such as vinylidene chloride, vinylidenecyanide, methylene malonic esters, etc.; vinylene compounds such asvinylene carbonates, maleic anhydride, maleic monoesters and maleicdiesters; the itaconic compounds such as itaconic anhydride, theitaconic monoand the itaconic diesters of the lower and higher aliphaticalcohols; the dienes such as butadiene, isoprene, 2-chlorobutadiene 1,3,and the like. The proportion of the new monomers in copolymers withother monomer will depend, in accordance with the accepted principles ofcopolymerization, on the reactivity and selectivity constants, r and rof the comonomers used in preparing the copolymer, the ratio of themonomers used and the extent of conversion. However, by selectingappropriate conditions for the copolymerization, copolymers, using thenew monomers of this invention can be made to contain eifective andsmall amounts of these new monomers, for example, of the order of from0.1% to 0.5% to very high amounts of the order of 99.5 to 99.9% in thefinal copolymers.

The new monomers of this invention can be polymerized by the knownmethods used to polymerize acrylic, methacrylic or itaconic compoundscontaining the CH =C group. The new monomers, in the presence or absenceof other polymerizable C=C containing monomers, can be polymerized inbulk, solution, emulsion, or suspension with or without polymerizationinitiators and other modifiers. As polymerization initiators there canbe used the per-compounds, such as potassium persulfate, tertiary butylperacetate, benzoyl peroxide, cumene hydroperoxide, tertiary butylperoxide, tertiary butyl perbenzoate, hydrogen peroxide with or withoutferrous salts, etc.; the azo catalysts such as alpha,alphaazobis(isobutyronitrile), ultraviolet light in the absence orpresence of ketones, ionizing radiation from X-rays, electron andparticle accelerators, cobalt 60 sources, etc.

In solution polymerization the medium can be selected from solventswhich "retain the polymer in .solution throughout the polymerization, orcan be chosen so that the polymer precipitates when formed and can beselected from the class of aliphatic, cycloaliphatic and aromatichydrocarbons, esters, ethers, ketones, halogenated hydrocarbons, etc.,or mixtures thereof depending on the form in which the polymer isdesired. When halogenated hydrocarbons are used, they also act asmodifiers of the polymerizations. In emulsion polymerization, theemulsifying agent to be used in the aqueous system is selected from theclass of fatty acid soaps, salts of sulfonated alkyl benzenes, polyvinylalcohol, gelatin, polyacrylic acid, salts of styrene-maleic acidpolymers, gelatin and the like, which can be used alone or withbuffering agents such as sodium acetate, borax, trisodium phosphate andthe like. In suspension polymerization, the dispersion agent can beselected from the class of insoluble inorganic carbonates, phosphatesand silicates to be used alone or in the presence of minor amounts ofdeflocculating agents such as sodium dodecylbenzene sulfonate orpotassium stearate.

The following examples illustrate the synthesis of the monomers,polymers, and copolymers of this invention and are not given by way oflimitation but by way of illustration. The parts and percentages givenare parts and percentages by weight unless otherwise specified.

EXAMPLE I There were combined in 500 parts of benzene, 84.0 parts ofitaconic anhydride and 88.5 parts of glyceryl carbonate,

HOCHzCHCHz in a reaction vessel equipped with stirrer, condenser, andheating means, and the mixture refluxed at 60 C. for 48 hours. Uponstanding at room temperature, crystalsof the ester product are formedand when separated from the benzene by filtration will be in an almostquantitative yield. The crude can be used as such or may be purified byrecrystallization from water. The ester product has a melting point of132l34 C.

Elemental analysis for C and H gives values of 46.85% and 4.57%respectively, which is in excellent agreement with the calculated valuesof 47.0% and 4.35% respectively, for the compound, 4-(1,3 dioxolone-2)methyl hydrogen itaconate, represented by the formula omon on, 0112000 1EXAMPLE II The procedure of Example I was repeated using 1,2 carbonateof 1,2,6 hexanetriol instead of glyceryl carbonate, and there wasobtained an itaconate represented by the formula which on analysis for Cand H and acid number determination give values in close agreement withthe theoretical values for the compound.

EXAMPLE III In a well-stirred reaction vessel containing 200 parts ofbenzene and 23 parts of the monomer of Example I was added 4.0 parts ofNaOH in 50 parts of ethyl alcohol to form the sodium salt. To thismixture was added slowly over a period of one hour 12.6 parts ofdimethyl sulfate and the mixture heated at 60-70 C. for two hours,following which it is allowed to cool to room temperature and filteredto remove solid salts. The benzene solution was washed with diluteaqueous sodium carbonate solution and with distilled water untilneutral; then dried with anhydrous sodium sulfate which is removed byfiltration. The benzene solution containing the crude product wastreated with activated carbon, filtered and concentrated at a reducedpressure of 15-30 mm., leaving the ester as a colorless viscous oildistillation of which was not possible without the pyrolytic eliminationof CO Elemental analysis of the viscous oil gives values of 49.06% C and4.92% H, which is in good agreement with the calculated values of 49.13%C and 4.914% H for the compound CH =C-C O CH3 H20 0 O CH2OHCH2 When anequivalent amount of diethyl sulfate was used for the dimethyl sulfatein this procedure, then the corresponding ethyl ester was obtained, as

CH2=C-C o 0 0 11 H2COOCH2?H(IJH2 EXAMPLE V To a reaction vessel equippedwith stirrer, condenser and inlet containing 1600 parts of benzene, 236parts of glyceryl carbonate, and 205 parts of triethyl amine and cooledto 0.5 C. was slowly added over a period of five hours 165 parts ofitaconyl chloride in 135 parts of benzene, following which the reactionmixture was allowed to come to room temperature during a period of fivehours. The mixture was filtered to remove and the filtrate washed withdilute aqueous Na CO solution until slightly alkaline and then withdistilled water until neutral. The benzene solution of the ester wasdried with anhydrous Na CO filtered and the filtrate separated frombenzene by distillation under reduced pressure, leaving a clear viscousoil which cannot be distilled at mm. without evidence of the pyrolyticelimination of CO Elemental analysis of the residual oil gave values forC and H of 46.96% and 4.18% respectively, which is in good agreement forthe calculated values of 47.27% and 4.24% for the compound When theglyceryl carbonate of this example is replaced by an equivalent amountof the homologous carbonates, such as then the corresponding itaconicdiesters are obtained.

EXAMPLE V To a reaction vessel equipped with a stirrer, condenser, andinlet was added 1000 parts of toluene, 112 parts of itaconic anhydrideand parts of octyl alcohol and the mixture heated under reflux for fivehours to produce the octyl hemi-itaconate,

CHz=C-C O OH GHzCO 0021117 To the reaction mixture then was added 119parts of thionyl chloride and refiux continued until 50;, and HOl wereno longer liberated from the reaction, leaving the acid chloride,

CH =C-C 0 C1 CHzCO 00 1111 in solution. The reaction solution was cooledto 0-5 C., and there was added slowly over a period of five hours amixture of 101 parts of triethyl amine and 118 parts of glycerylcarbonate in 200 parts of ethyl ether, following which the mixture wasallowed to come to room temperature. The mixture was then filtered toremove washed and dried according to the procedure of Example 1V, afterwhich the solvent was removed by distillation under reduced pressure,leaving a clear viscous oil which is not distillable at 5 mm. pressurewithout evidence of pyrolytic CO evolution. Elemental analysis forcarbon and hydrogen give values of 59.8% and. 7.55% respectively, whichis consistent with the formula The copolymerization of the monomers ofthis invention is illustrated by the use of the itaconic ester ofglyceryl carbonate of Example I, with a number of monomers such asstyrene, vinyl acetate, methylacrylate and methyl methacrylate asexamples of monomers containing a CH =C group. The r and r values of thepair of monomers were determined by the methods given in J.A.C.S. 66,1594 (1944) and 67, 1701 (1945).

EXAMPLE VI Styrene and the itaconic ester of glyceryl carbonate, weremixed in the mole ratios 0.4:1, 0.5: 1, 06:1, 0.86: 1, 1:1, 3:1, 7:1,10:1, and 15:1 respectively, and sufiicient purified acetone added toproduce a 20% solution of monomers in solvent. The mixtures werepolymerized at 50 C. using an amount of benzoyl peroxide equivalent to0.25% by weight of the monomer as the catalyst and the r for styrene andr for the carbonate were determined as 0.445 and 0.53 respectively bythe methods referred to hereinabove. The copolymers obtained from thesevarious ratios were soluble in a variety of solvents such as acetone,dioxane, toluene, dimethyl formamide, dimethyl sulfoxide, ethylenecarbonate, etc but extended heating at elevated temperatures in therange of from 130 to 180 C. resulted in crosslinking and/or foaming ofthe polymeric compositions and the insolubilization thereof.

EXAMPLE VII Copolymers of methacrylate and the itaconic ester ofglyceryl carbonate exhibited r values as determined by the procedure ofExample VI of 0.41:0.06 for r and 1.64:0.4 for r EXAMPLE IX The valuesof r for methyl methacrylate and r for the itaconate as determined bythe procedure of Example VI are 1.38:0.25 and 0.24:0.15 respectively.

With these known values of r and r for the various monomer pairs,copolymers of desired composition can be readily prepared according tothe standard procedures known in the art,

EXAMPLE X As an illustration of solution copolymerization, 95 parts ofstyrene, parts of the monomer of Example III,

and 200 parts of toluene containing 1 part of2,2'-azobisisobutyronitrile were heated in a reactor at 75-80 C. for 24hours, producing a clear colorless polymer solution useful directly as acoating composition which can be converted to an insoluble product byheating to temperatures of 180190 C. A product suitable for molding canbe obtained from the toluene solution by precipitation with methylalcohol.

EXAMPLE XI As an illustration of emulsion polymerization, 90 parts ofvinyl acetate, parts of CH =CC 0 0 c n,

H20 0 O CH2(|3HCH2 the ethyl ester embodiment of Example III, parts ofwater containing 1.5 parts of polyvinyl alcohol and 0.5 part ofpotassium sulfate were heated in a suitable reactor at 75-80 C. for 12hours producing a latex which can be used directly as an adhesive.

EXAMPLE XII Thirty parts of the monomeric methyl ester of Example III, 1part of benzoyl peroxide are mixed and heated at 80 C. for 72 hours,producing a thick viscous polymer which on continued heating at C.became insoluble in toluene. The intermediate viscous polymer issuitable as a casting resin.

From the foregoing examples it may be seen that the new monomeric estersof this invention are quite versatile, their inherent characteristicsenable the production of a Wide range of polymers and copolymers. Byvarying the conditions of polymerization, such as the nature of thecatalyst, as well as its concentration, the temperature ofpolymerization, the choice of the medium, if any, in which thepolymerization is performed, and the selection of as well as the ratioof monomeric compounds employed, the physical and chemical properties ofthe ultimate polymer can be controlled. Additionally as has been pointedout hereinabove these new monomeric esters contain a CH :C groupingpermitting their polymerization by the regular procedures used inpolymerizing acrylic and itaoonyl monomers; moreover, since they containa cyclic carbonate structure, they can undergo secondary reactionsutilizing the carbonate ring rather than the CH :C grouping. One featureof this secondary reaction involves the elimination of CO from themonomer on heating. In the absence of other reagents which modify thecourse of the reaction; the neutral esters of this invention such asbegin to evolve CO noticeably in the temperature range of 200-210 0,whereas if one of the carboxyl groups is left unesterified, for exampleas in the elimination of CO is noticeable in the temperature range of150 C.; and this reaction is probably due,

9 and favored by, the transesterification of the free --COOH group withthe cyclic carbonate ring CHCH2 l) l with release of C The variation intemperature required to eliminate CO is carried into the polymers andcopolymers of the monomeric esters of this invention when they contain afree carboxylic group. This phenomena is also observed when the carboxylgroup is not part of the monomeric ester but is present as an element ofa CH :C containing monomer, such as acrylic acid, methacrylic acid,itaconic acid, itaconic acid monoester, maleic acid, fumaric acid,maleic acid monoester, which has been copolymerized with the neutral, ordiesters of this invention. It was also discovered, in the use of thenew monomers and polymers of this invention, that the temperature of COliberation could be greatly reduced in the presence of chemicalmodifiers such as acid and salts, for example, H PO Na CO NaHCO ZnClFeSO etc. As illustrative of this improvement, the addition of 1% ZnClto CHz=CCOOCH3-( ]H( ]Hn HzCOOCHzCHCH2 II 0 reduces the CO eliminationtemperature from about 200 C. to about 110 C. These modifiers therebyincrease the utility of the monomers and polymers of this invention byavoiding thermal pyrolysis of the compounds through lowering of thetemperature needed to generate CO when a foamed polymer is desired.Though the monomers of this invention are particularly useful in thepreparation of polymers for the coating, laminating, molding and foamedpolymer arts, they are useful in themselves as foaming agents to beadded alone or with modifiers to other preformed polymers to producefoamed composition.

It will be obvious that variations in the component elements of thenewly described compounds, the manner of their preparation andutilization are possible without departing from the spirit of theinvention or the scope of the appended claims.

What I claim is:

1. As new compounds, monomeric esters having structures designated bythe formula CH =C-C O O- l 2 i RI CH2COO in which R is a member of theclass consisting of hydrogen, a saturated hydrocarbon radical containingfrom one to eight carbon atoms and R, and R represents 2)n l z o o o H oin which n is an integer having a value of from 1 to 4 inclusive.

2. A monomeric ester having a structure designated by the formulaliCHr-C-COO-I R in which R is a member of the class consisting of hydrogen, a saturated hydrocarbon radical containing from one to eight carbonatoms and R, and R represents 3. A monomeric ester having the formula 4.A monomer having the formula 5. A monomer having the formula l llilll-l6. The polymerization product of a monomer claim 1.

7. The polymerization product of a monomer claim 2.

8. The polymerization product of a monomer claim 3.

9. The polymerization product of the monomer claim 4.

10. The polymerization product of the monomer of claim 5.

11. A copolymer of a monomer of claim 1 and at least one copolymerizableethylenically unsaturated compound.

12. A copolymer of a monomer of claim 2 and at least one ethylenicallyunsaturated compound copolymerizable with a monomer of claim 2.

13. A copolymer of a monomer of claim 3 and at least one vinyliden'ecompound copolymerizable with monomers of claim 3.

14. A copolymer of the monomer of claim 4 and at least one ethylenicallyunsaturated compound copolymerizable with the monomer of claim 4.

15. A copolymer of the monomer of claim 5 and at least one ethylenicallyunsaturated compound copolymerizable with the monomer of claim 5.

16. A copolymer as defined in claim 12 in which the ethylenicallyunsaturated compound is styrene.

17. A copolymer as defined in claim 13 in which the ethylenicallyunsaturated compound is styrene.

References Cited by the Examiner UNITED STATES PATENTS 2,403,112 7/ 1946Muskat 26077.5 2,967,173 1/1961 Fang 260-775 2,979,514 4/1961 OBrien etal 260--77.5

FOREIGN PATENTS 611,033 12/1960 Canada.

LEON J. BERCOVITZ, Primary Examiner.

J. R. LIBERMAN, Examiner.

1. AS NEW COMPOUNDS, MONOMERIC ESTERS HAVING STRUCTURES DESIGNATED BYTHE FORMULA
 6. THE POLYMERIZATION PRODUCT OF A MONOMER OF CLAIM
 1. 11. ACOPOLYMER OF A MONOMER OF CLAIM 1 AND AT LEAST ONE COPOLYMERIZABLEETHYLENICALLY UNSATURATED COMPOUND.